The expansion-type rock bolt made of reinforcing steel pipes, developed by K.F.C. Co., Ltd., contributes to the longevity of tunnels.
This is a new concept tunnel rock bolt that expands due to high water pressure and has a mechanism for securing itself to the surrounding rock. 【Features】 ★ Reliable construction without filling materials ★ It secures itself to the surrounding rock with the expansion pressure of the steel pipe, without using filling materials like mortar. Even in areas with water inflow, it secures itself reliably without the influence of cement component leakage. ★ Speedy construction ★ Since no fixing materials like mortar are needed and it secures itself simultaneously with construction, it contributes to shortening the construction cycle and achieving early strength development. ★ High corrosion-resistant rock bolt ★ The entire length of the bolt is treated with high corrosion-resistant plating, boasting high durability. This contributes to the long lifespan of tunnel structures. *For more details, please download the PDF or contact us.
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basic information
When high-pressure water is injected using a dedicated high-pressure water injection system, the expansion section of the rock bolt inserted into the ground expands along its entire length, securing it to the ground. By providing a male thread at the mouth, it becomes possible to tighten the lining concrete with a nut, which is expected to enhance the effectiveness of ground support. 【Accessories】 Injection adapter High-pressure water injection system for expansion Anti-loosening nut "K nut" Protective pipe for lining concrete Multifunctional G type (tip cap detachable type)
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※The delivery time may vary depending on the quantity, so please feel free to contact us.
Applications/Examples of results
It is suitable for cases where construction is required within a limited time due to traffic regulations, such as repairs to in-use road tunnels and railway tunnels. Since the excavation of the ground and lining can be completed in one go, and tensile tests can be conducted without waiting for the curing of the setting material, the construction period can be shortened (compared to our other methods). It has been adopted for large-scale renovation work on the Tōkaidō Shinkansen and for renovation work on highway tunnels.
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Company information
As a pioneer in post-installed anchors in Japan, KFC was founded in 1965. We respond to customer needs with a consistent system from product development to sales and construction. Our business activities focus on three main areas: construction fastening materials such as post-installed anchors, materials for tunnel excavation like rock bolts and auxiliary methods, and various construction projects related to seismic reinforcement, safety measures, equipment, and refreshment.